This is the renewal application for a multidisciplinary training program in Pulmonary and Critical Care Medicine (PCCM) at the David Geffen School of Medicine (DGSOM) at UCLA. The training program will continue to provide training in basic science and clinical research relevant to the study of PCCM-related diseases. The program proposes to continue to support a total of six postdoctoral trainees (M.D.s, Ph.D.s and M.D./Ph.D.s) for a two year experience in a highly structured environment under the close supervision of faculty mentors. The trainees will take advantage of experienced faculty mentors whose research encompasses themes of 1) Infection/Inflammation/Transplantation (Belperio, Cheng, Deng, Horwitz, and Modlin), 2) Lung Carcinogenesis (Dubinett, Gomperts, and Sharma), 3) Iron Metabolism (Ganz, Nemeth) and 4) Health Services Research and Prevention (London, Needleman, and Wenger). The program will continue to utilize faculty mentors from several Departments in the DGSOM, and the School of Public Health at UCLA. The faculty mentors have extensive research experience in diverse yet overlapping areas of molecular and cellular biology, biostatistics, epidemiology, clinical study design or medical ethics. The faculty mentors have previously trained postdoctoral trainees, who have subsequently gone on to independent and productive careers in academia or industry. The environment at UCLA together with the faculty mentors will continue to offer an outstanding experience for trainees in research disciplines relevant to PCCM-related diseases. The program will continue to provide a structured curriculum that contains appropriate course work, exposure to relevant lecture series and an intensive basic science or clinical research experience. The training program has been highly successful in developing new investigators with the vast majority of trainees continuing in research careers in academia or industry.